The function of gyro spin bearings is to provide a stable and rigid axis of rotation for the gyro rotor with low friction and adequate life. Bearings must be stable in order to reduce mass shifts, and they should be rigid and have the proper elastic ratios in order to minimize compliance effects. They should have a low friction torque in order to reduce to a minimum the weight of the motor and the effects of temperature gradients due to the power input, and they must have a life adequate for the particular application.
Induction motors and synchronous hysteresis motors have been used in the past to spin the gyro rotor. However, in these devices there is a need for a bearing means that lends itself to this type construction and that does not produce temperature gradients that are undesirable, and a bearing that has low friction torque. Also, there is a need for a caging mechanism that has low friction means also.
Therefore, it is an object of this invention to provide a rotor and stator in which one of these members has the motor windings mounted therein and the other member has magnets thereon with magnetic fluid between the two surfaces to act as a bearing.
Another object of this invention is to provide a bearing between the rotor and its caging member and a bearing such as a magnetic fluid so as to virtually eliminate kick during uncaging of the rotor.
Other objects and advantages of this invention will be obvious to those skilled in this art.